uwam2ie,
Rules for file management alone can only be effective in a small, well-disciplined work group who know and follow all of the rules. Once an important file is mistakenly deleted, it loses that effectivity. PDM enforces those rules, eliminating the very real danger of accidentally revising or deleting files which are supposed to be controlled. There are many more benefits to PDM than that, such as organizing your files, having a searchable history, and controlling processes (approvals and revisions).
A real life example that I am cleaning up now: We use UG and SolidWorks. A new project manager downloads UG part files from a customer onto the server. These parts are actually "dumb" copies of our own parts (same names), which the customer had approved and sent back to us to document the "as built" condition, and should never been mixed up with our production files. Another engineer is working on a UG assembly which contains some of the original parts. When he opens the assembly, some of the "dumb" parts are loaded. He makes his changes and saves the file.
Meanwhile, another engineer opens a released UG assembly in SW. Of course, SW makes copies of all of the parts in that assembly and puts them in the same (released and protected) folder as the original UG file.
Now I have to reconstruct the first engineers assembly to reflect the correct associative parts, and then I have to go through the released directory and delete all of those SW files that do not belong there.
Wasted time and effort that would have been avoided with a decent PDM system.
